Dental drill.



H. E. S. CHAYES.

DENTAL DRILL.

APPLICATION FILED OCT. 23. 1913.

Patented May 16, 1916.

Fig- 2L Fig- 1- A rron/vfr WITNESSES HERMAN E. SQCHAYES, OF NEW YORK, N. Y.

DENTAL DRILL.

Application filed October 23, 1913.

To all whom it may concern:

Be it known that I, HERMAN E. S. CHAYES, a citizen of the United States of America, and resident of New York, in the county of New Yorkand State of New York, (whose post-office address is No. 576 Fifth avenue, New York, N. Y.,) have invented certain new and useful Improvements in Dental Drills, of which the following is a specification.

This invention relates to hand-pieces for dental engines, and the principal object of the invention is to provide a hand-piece which is adapted to carry and actuate a plurality of tools, as, for instance, a plurality of burs.

More specifically, my invention aims to provide a l1and-piece in which provision is made for carrying and driving a plurality of tools, as, for instance, burs, in such a manner that the plurality of burs may be simultaneously driven from a common driving means and whereby the burs or other tools may be, with great facility, adjusted to various positions relatively to each other.

A further object of the invention is to provide an instrument of the kind referred to, having such structural characteristics that vibration is minimized, and the possibility of injury to the soft tissues in the mouth by moving parts is prevented.

Other objects and aims of the invention, more orless broad than those stated above, together with the advantages inherent, will be in part obvious and in part specifically referred to in the course of the following description of the elements, combinations, arrangements of parts, and applications of principles constituting the invention; and the scope of protection contemplated will appear from the claims.

In the accompanying drawing, which is to be taken as a part of this specification, and in which I have shown one of the various possible embodiments of this invention as at present referred: Figure 1 is a sectional view, with parts broken away, taken on the line 1-1 of Fig. 2 and looking in the direction of the arrows; Fig. 2 is a central sectional view of a hand-piece embodying the invention, showing certain of the parts in elevation and with the main driving shaft broken away; Fig. 3 is a perspective view, illustrating this embodiment of my inven-v tion; and Fig. 1 i detail view of the .key

Specification of Letters Patent.

Patented May 16, 1916.

Serial No. 796,799.

for locking the tools carried by the handplece n their various adjusted positions. S1m1lar reference characters refer to simllar parts throughout the several views of the drawing.

Referring to the numerals on the drawing,

there is shown at 5 a supporting frame into which is screw-threaded a hollow guard or handle 6. Through this handle 6 passes the main driving shaft 7, which carries at its end within the frame 5, a gear 8 that serves to drive a shaft 9 which has bearings at one end in the frame 5 and at the other end in a nut 10 that is threaded into the frame. This shaft 9 has a gear 11 cooperating with the gear 8, and carries also a gear 12. The rotation of the shaft 9 is communicated by means of the gear 12 to a large gear-wheel 14 that is pivoted on a pin 15 which passes through arms 16 on the frame 5 and is secured as by means of a kerfed nut 17. This pin 15 carries also, in the form shown in the drawing, a pair of bifurcated arms 18, which arms may be swung about the pin 15 as a center. The branches of the arms 18 pass on opposite sides of the gear-wheel 14, and the portions of these arms at the pivotal center are spaced away from the arms 16 by means of spacing blocks 19. Overlying the opposite faces of the gear-wheel 14 is a pair of cover disks 20, centrally apertured for the passage of the pin 15 and projecting at their edges slightly beyond the periphery of the gear-wheel 1 1. At the central portion of the gear-wheel there is also a" bushing 21 of slightly greater thickness than that of'the gear-wheel 14, and a pair of washers 22, which bear between the disks 20 and the bushing 21. By this arrangement it will be obvious that if the nut 17 is tightened down, the arms 18. may be clamped in position, but the gear-wheel 14 will be free to rotate. The rotation of the gear 1 1 is communicated directly to rotary sockets or tool-holders 24 which are carried in the recessed head portions 18' at the outer ends of arms 18.

7 Each socket member is substantially a sleeve provided at its outside with a gear 25 through which it is driven by means of the gear 1 1, and having also a shouldered portion 26 which constitutes a bearing for it within a correspondingly shaped recess within the end of the arm, the other end of the socket member being held i position by means of the engagement of a shouldered portion 27 thereof with the inner end of an apertured nut 28 that is threaded into the end of the arm as shown in Fig. 2. The shank of a tool, such as a bur, is inserted through the aperture in the nut 28 and into the interior of the socket member- 24. As is usual in instruments of this kind, the inner, end of the shank has a flattened portion which engages a corresponding flattened projection in the inner end of the socket or tool-holder whereby the bur or tool is caused to rotate with the toolholder. In the end of the tool shank, as usual, is an annular groove, adapted to be engaged by a notched swing-slide 29, pivoted by a screw 30 Within a slot in the end of each arm 18.

I have shown in Fig. 1 the outer ends of the two arms 18 after the arms have been swung about the central pin 15 to the position in which they are most closely contiguous, and in the same figure I have shown in dotted lines another position of the arms in which their ends, and consequently the tools carried thereby, are separated. The widest separation will of course be diametrically of the large gear 14, but whatever the position of the arms, the gears 25 of the tool-holders 24: carried thereby will always be in operative engagement with the large gear 14. The adjustment of the arms may be readily changed by engaging the key shown in Fig. 4 with the kerfed nut 17 to loosen the arms whereupon they may be swung about their pivotal center as desired, and fixed in position again by jamming the nut 17. By reason of the fact that the tools run on an angle to the main driving shaft, the distal part of the mouth is readily accessible to the operator. The arrangement of the parts so that the tools are adjustable about the periphery of each gear wheel is very important, first, because I obtain thereby the widest possible range of adjustment with a main gear of given size, and secondly, because with this arrangement the view of the work being done is not obscured or covered up by the large gear wheel. The large gear wheel 14' is covered and overhung by the two disks 20 so that the latter expand slightly beyond the teeth of the gear in order to obviate the possibility of injuring the soft tissues when the instrument is in use. Vibration of the drills is greatly reduced, because the power is transmitted from the main shaft to the large gear-wheel, and thence to the small gears of the tool holders, which latter are always at the same distance from the center of the main gear, no matter what their positions relatively to each other may be. Furthermore, since the arms that carry the tool holders are secured at the center of the large gear, and because the gears of the tool-holders are in close contact with the teeth of the large gear, friction is further reduced because the arms are in effect supported at two points, namely, at the pin 15 and at the periphery of the large gear-wheel.

The manner of using this instrument will be obvious to the dentist, and therefore I do not deem it necessary to enter into a detailed explanation. I may suggest, however, that by the use of this instrument, it is possible to drill or otherwise to operate upon a plurality of teeth simultaneously, which is of itself a decided advantage. Furthermore, with this instrument I may drill into a plurality of teeth at the same time and be assured of absolute parallelism of out, which is of great importance, for instance, in connection with bridge work.

Inasmuch as many changes could be made in the above construction, and many apparently widely different embodiments of my invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim 1. In a dental engine hand-piece, the combination of a hollow handle portion, a frame connected to said handle portion and including a pair of arms, a driving shaft entering the frame through the handle, a pivot pin passing through the arm portions of the frame, a gear wheel rotative about said pivot pin, a pair of arms mounted to swing about said pivot pin, a rotary toolholder carried within each of said arms, and means carried by each tool-holder cooperating with said gear wheel to rotate the toolholder.

2. In a dental engine hand-piece, the combination of a hollow handle portion, a frame connected to said handle portion and including a pair of arms, a driving shaft entering the frame through the handle, a pivot pin passing through the arm portions of the frame, a gear wheel rotative about said pivot pin between the arms, a bifurcated tool-holding member having its legs embracing the gear wheel and embraced between the arms of the frame and pivoted upon the said pivot pin, said tool-holding member including a rotary socket member, and a gear carried by the rotary socket member in operative engagement with the gear wheel aforesaid.

3. In a dental engine hand-piece,the combination of a hollow handle portion and a frame connected therewith having spaced arm portions, a pivot pin passing through said arm portions, a gear wheel pivoted upon said pin between the arm portions, driving means for the gear wheel passing through the handle, a tool-holding element having spaced arms embracing, the gear wheel and embraced between the arms of the frame and pivoted on said pin, said tool-holding element including also a rotary socketed member, a gear formed on the exterior of the socketed member in engagement with the teeth of the gear wheel aforesaid, and means for locking the tool-holding element in desired angular relation about the pivot.

4:- In a dental engine hand-piece, the combination of ahollow handle portion, a frame connected therewith and having spaced arm portions, a driving shaft entering the frame through the handle, a pivot pin passing through the arm portions, a gear wheel pivoted on said pin between the arm portions and having teeth on its periphery, a tool holding member adjustable to different positions about the periphery of the gear wheel, said tool-holding member being connected to the pivot pin, and said tool-holding member including a rotative socketed member, and a gear. on the exterior of-the socketed member and engaging with the teeth of the first-mentioned gear wheel.

5. In a dental engine hand-piece,the combination of a hollow handle portion,a frame connected therewith and having spaced arm portions, a driving shaft entering the frame through the handle, a pivot pin passing through the arm portions, a gear wheel pivoted on said pin between the arm portions and having teeth on its periphery, a toolholding member adjustable to different positions about the periphery of the gear wheel, said tool-holding member being connected to the pivot pin, and said tool-holding member including a rotative socketed member and a gear on the exterior of the socketed member and engaging with the teeth of the first mentioned gear wheel, and means for locking the tool-holding member in desired position about the periphery of the first-mentioned gear wheel.

6. In a dental engine hand-piece,the combination of a hollow handle portion, a frame connected therewith and having spaced arm portions, a pivot pin passing through the arm portions, a gear wheel pivoted upon said pin between the arm portions, a driving shaft for actuating said gear wheel en tering the frame through said handle, a cover disk on each side of the gear wheel and overhanging the same, a tool-holding element having a portion pivoted on the said pivot pin and as a whole angularly adjustable around the pin, saidtool-holding element including a socketed member, a gear on the exterior of the socketed member and in engagement with the teeth of the first-mentioned gear-wheel in any adjusted position of the tool-holding member as aforesaid, and means for locking the tool-holding member in a desired adjusted position.

7 In a dental engine hand-piece, the com bination of a hollow handle portion, a frame connected therewith and having spaced arm portions, a pivot pin passing through the arm portions, a gear wheel pivoted upon said pin, a shaft entering the frame through the handle for actuating the gear wheel, a plurality of tool-holding elements, each tool holding element including spaced arm portions pivoted on the pivot pin, one arm on each side of the gear wheel between the arm portions of the frame, each tool-holding member including also a recessed head portion, a rotative socketed member within such recessed portion, a gear on the exterior of such socketed member engaging the gear wheel first-mentioned, and means for holding the rotary socketed member within such recessed portion.

8. The combination of a hollow handle portion, a frame connected therewith having spaced arm portions, a pivot pin extending through the arm portions, a gear wheel mounted upon the pivot pin between the arm portions, a shaft extending through the handle for actuating the gear wheel, a spoollike member forming the hub of the gear wheel, the flanges of the spool-like member being spaced apart a distance greater than the thickness of the gear wheel, a tool-holding member including spaced arm portions pivoted on the pin, one arm on each side of the spool-like member, and means for exerting a clamping action upon the arm portions of the frame, thereby to clamp the arms of the tool-holding member between the arms of the frame and the flanges of the spool-like member to lock the arms of the tool-holding member in a given relation to the pin, said tool-holding member having also a rotary portion, and a gear formed exterior-1y of the rotary portion in engagement with the teeth of the first-mentioned gear.

9. In a dental engine hand-piece, the combination of a hollow handle, a drive shaft extending therethrough, a frame connected to the handle and having spaced arm portions, a pivot pin extending through the arms, a flat gear pivoted on the pin between the arms and driven by said shaft, a plurality of tool-holding elements supported on the pin between the arms, and having rotary portions engaged by the teeth of the gear Wheel.

10. In a dental engine hand-piece, the combination of a hollow handle, a drive shaft extending therethrough, a frame connected to the handle and having spaced arm portions, a pivot pin extending through the arms, a flat gear pivoted on the pin between the arms and driven by said shaft, a plurality of tool-holding elements pivotally movable on the pin between the arms, and having rotary portions engaged by the teeth of the gear in pivoted position, and

means for locking the said elements in desired pivotal position.

11. In a dental engine hand-piece, the combination of a hollow handle, a drive shaft extending therethrough, a frame connected to the handle and having spaced arm portions, a pivot pin extending through the arms, a flat gear pivoted on the pin between the arms and driven by said shaft, a plurality of tool-holding elements adjustably supported on the pin between the arms, and having rotary portions engaged by the teeth of the gear in all of their adjusted positions.

12. In a dental engine hand-piece, the combination of a hollow handle, a drive shaft extending therethrough, a frame connected to the handle, a plurality of toolholding members supported by the frame and movable so that they may be spaced apart to a greater or less extent, each toolholding member including a rotary part operatively connected to the drive shaft, whereby the drive shaft causes the rotation of such rotary part in the different adjusted positions of the latter.

13. In a dental engine hand-piece, the combination of a hollow handle, a driveshaft extending therethrough, a frame connected to the handle, a plurality of toolholding members supported by the frame and movable so that they may be spaced apart to a greater or less extent, each toolholding member including a rotary part operatively connected to the drive-shaft and extending at an angle thereto, said driveshaft adapted to cause the rotation of such rotary parts in different adjusted positions of the latter.

In witness whereof I have hereunto signed my name in the presence of two witnesses.

HERMAN E. S. CHAYES.

Witnesses:

KATHARINE M. SoHILLo, ALDA L. MILLER.

Copies of this patent may be obtained for five cents each. by addressing the Commissioner of Patents Washington, D. 0. 

